I. Field of the Invention
The present invention relates generally to the field of hunting tree stands with which hunters, wildlife photographers or other observers can climb trees in order to position themselves in an observation position where they will not be seen by animals as a threat to scare them from coming near. In particular, it is a dual frame tree climbing tree stand with tree spikes which form triangular shapes for rigidity of the stands and also form effective angles of entry of the tree spikes into trees of different diameters. Related features result in ease of packing, low weight, convenience of use, comfort and other advantages.
II. Description of the Prior Art
There are a wide variety of successful dual frame hunting tree stands in use. This invention, however, has different structure and working relationships of parts that provide advantages previously unavailable.
Examples of different but pertinent prior art include the following United States patent documents:
______________________________________ U.S. PAT. NO. DATE NAME CLASSIFICATION ______________________________________ 4,997,063 Mar. 5, 1991 Bradley 182/187 4,492,942 Jul. 24, 1990 Bradley 182/187 4,969,538 Nov. 13, 1990 Amacker 182/187 4,331,216 May 25, 1982 Amacker 182/135 4,316,526 Feb. 23, 1982 Amacker 182/135 ______________________________________
The Bradley U.S. Pat. No. 4,997,063 had a conventional turnbuckle means for leveling both frames of dual frame hunting stands, a conventional net bottom frame and a seat for the top frame different from those provided as optional embodiments of this invention. They are used in different working relationships of parts. The turnbuckle in the Bradley U.S. Pat. No. 4,997,063, for example, was employed in relationship to a pin hinged anchor rather than an angled prong anchor as employed in this invention. The structure of this invention is different for its different working relationships of parts.
The Bradley U.S. Pat. No. 4,492,942 had a still different means for leveling a frame. A central leveling yoke was adjusted with a leveling pin with a different form than used for different embodiments of this invention.
The Amacker U.S. Pat. No. 4,969,538 taught a triangular structure for attachment of tree hugging braces, but they were not foldable differently for backpacking mode and operational mode as provided by this invention.
The Amacker U.S. Pat. No. 4,331,216 employed tree engaging prongs that were directed towards centers of trees differently than provided by this invention. They were not ends of structural members that provide structural rigidity as in this invention.
The Amacker U.S. Pat. No. 4,316,526 employed tree engaging prongs that were directed towards centers of trees for maximizing grasping efficiency in a different way than this invention. It decreased rather than increased structural integrity.